QuakeIndex

Earthquake · reviewed by a seismologist

M 2.9md

Earthquake near Guánica, PR

No earthquake was likely felt in Guánica in the 24 hours to 6:00 am AST (10:00 UTC). The last one was M 2.1, 13 km (8 mi) ENE, at 4:39 pm AST on 9 November 2026, estimated intensity II (weak) in town. Every earthquake near Guánica

This page: a magnitude 2.9 earthquake was recorded 6 km (4 mi) west of Guánica, PR, at 11:14 pm AST on 28 June 2021 (03:14 UTC), 10 km deep.

USGS: Puerto Rico region

36 km (23 mi) W of Ponce, PR · 31 km (20 mi) SE of Mayagüez, PR

11:14 pm AST, Jun 28, 2021 · · 10 km deep · released about 720 lb of TNT

Every earthquake near Guánica Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Guánica Municipio 5 kmLajas Municipio 8 kmSabana Grande Municipio 12 kmSan Germán Municipio 17 kmYauco Municipio 17 kmGuayanilla Municipio 18 kmMaricao Municipio 22 kmCabo Rojo Municipio 23 kmHormigueros Municipio 24 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
11:14 pm AST on 28 June 2021 ()
Where
6 km (4 mi) west of Guánica, PR · earthquakes near Guánica
Magnitude
M 2.9 (md)
Depth
10 km below the surface
Felt
no reports yet
Nearest
Guánica Municipio, 5 km ESE
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1961 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth, people at rest would likely notice it out to about 31 km (19 mi) from the epicentre. In Guánica, 6 km away, the estimate is intensity III (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

Likely felt in: Yauco 14 km, intensity II · San Germán 15 km, intensity II · Guayanilla 19 km, intensity II · Magas Arriba 21 km, intensity II · Pole Ojea 23 km, intensity II · Puerto Real 26 km, intensity II · Tallaboa 26 km, intensity II · Tallaboa Alta 29 km, intensity II. Estimated for each town centre; each link is that town's own record.

How big was it?

This earthquake released about 720 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.9 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 21,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 15,000× the energy of this one
  3. Around the size people start to feel M 3.0 1.3× the energy of this one
  4. This earthquake M 2.9 about 720 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

The largest earthquake within 50 km in our catalogue was M 6.4 on 2020-01-07 — about 170,000 times the energy of this one.

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 17.9740, -66.9653. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Guánica Municipio, PR 5 km (3 mi) ESE earthquakes near Guánica Municipio
Lajas Municipio, PR 8 km (5 mi) W earthquakes near Lajas Municipio
Sabana Grande Municipio, PR 12 km (8 mi) N earthquakes near Sabana Grande Municipio
San Germán Municipio, PR 17 km (10 mi) NNW earthquakes near San Germán Municipio
Yauco Municipio, PR 17 km (10 mi) NE earthquakes near Yauco Municipio
Guayanilla Municipio, PR 18 km (11 mi) E earthquakes near Guayanilla Municipio

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

60 earthquakes have been recorded within 50 km since this one.

  1. 2.3 6 km SE of Indios, Puerto Rico
  2. 2.6 4 km WSW of La Parguera, Puerto Rico
  3. 2.5 2 km NE of Fuig, Puerto Rico
  4. 2.7 2 km NE of Magas Arriba, Puerto Rico
  5. 2.8 2 km WSW of La Parguera, Puerto Rico
  6. 2.4 6 km WSW of La Parguera, Puerto Rico
  7. 2.3 11 km SSE of Maria Antonia, Puerto Rico
  8. 3.0 2 km NNW of Indios, Puerto Rico
  9. 3.2 3 km SE of La Parguera, Puerto Rico
  10. 2.4 1 km WSW of Indios, Puerto Rico
  11. 2.5 3 km W of Fuig, Puerto Rico
  12. 2.9 3 km W of Fuig, Puerto Rico
  13. 2.9 3 km ENE of La Parguera, Puerto Rico
  14. 2.9 4 km W of Pole Ojea, Puerto Rico
  15. 2.9 4 km SE of La Parguera, Puerto Rico

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.